U.S. patent number 11,038,334 [Application Number 16/247,201] was granted by the patent office on 2021-06-15 for aircraft wing composite ribs having electrical grounding paths.
This patent grant is currently assigned to THE BOEING COMPANY. The grantee listed for this patent is The Boeing Company. Invention is credited to Steven Paul Walker.
United States Patent |
11,038,334 |
Walker |
June 15, 2021 |
Aircraft wing composite ribs having electrical grounding paths
Abstract
Aircraft wing composite ribs having electrical grounding paths
are described. An example composite rib includes a carbon fiber
reinforced plastic (CFRP) panel, a metallic rib post, a metallic
fitting, and a metallic grounding member. The metallic rib post is
coupled to the CFRP panel and configured to be coupled to a spar of
an aircraft wing, the spar being coupled to a current return
network (CRN) cable. The metallic fitting is coupled to the CFRP
panel and configured to be coupled to a skin panel of the aircraft
wing. The metallic grounding member is positioned between the CFRP
panel and the metallic fitting. The metallic grounding member
provides an electrical grounding path extending from the metallic
fitting to the metallic rib post.
Inventors: |
Walker; Steven Paul (Arlington,
WA) |
Applicant: |
Name |
City |
State |
Country |
Type |
The Boeing Company |
Chicago |
IL |
US |
|
|
Assignee: |
THE BOEING COMPANY (Chicago,
IL)
|
Family
ID: |
1000005620126 |
Appl.
No.: |
16/247,201 |
Filed: |
January 14, 2019 |
Prior Publication Data
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Document
Identifier |
Publication Date |
|
US 20200227905 A1 |
Jul 16, 2020 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H02G
13/80 (20130101); B64C 3/187 (20130101); H01R
4/308 (20130101) |
Current International
Class: |
H02G
13/00 (20060101); B64C 3/18 (20060101); H01R
4/30 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1942052 |
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Jul 2008 |
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EP |
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1942052 |
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Jul 2008 |
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EP |
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2914622 |
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Oct 2008 |
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FR |
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Other References
European Patent Office, "Extended European Search Report," issued
in connection with European Patent Application No. 20151064.1,
dated Jun. 8, 2020, 5 pages. cited by applicant .
United States Patent and Trademark Office, "Non-Final Office
Action," issued in connection with U.S. Appl. No. 16/247,222, dated
Sep. 30, 2020, 6 pages. cited by applicant .
United States Patent and Trademark Office, "Notice of Allowance and
Fee(s) Due," issued in connection with U.S. Appl. No. 16/247,222,
dated Dec. 11, 2020, 5 pages. cited by applicant.
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Primary Examiner: Mayo, III; William H.
Assistant Examiner: Robinson; Krystal
Attorney, Agent or Firm: Hanley, Flight & Zimmerman,
LLC
Claims
What is claimed is:
1. A composite rib, comprising: a carbon fiber reinforced plastic
(CFRP) panel; a metallic rib post coupled to the CFRP panel and
configured to be coupled to a spar of an aircraft wing, the spar
coupled to a current return network (CRN) cable; a metallic fitting
coupled to the CFRP panel and configured to be coupled to a skin
panel of the aircraft wing; and a metallic grounding member
positioned between the CFRP panel and the metallic fitting, the
metallic grounding member providing an electrical grounding path
extending from the metallic fitting to the metallic rib post.
2. The composite rib of claim 1, wherein the electrical grounding
path is configured to carry lightning current from the metallic
fitting to the metallic rib post, the lightning current to be
received at the metallic fitting from the skin panel, to pass
through the electrical grounding path, and to pass from the
metallic rib post through the spar to the CRN cable.
3. The composite rib of claim 1, wherein the electrical grounding
path is configured to carry electrostatic charge from the metallic
fitting to the metallic rib post, the electrostatic charge to be
received at the metallic fitting from the skin panel, to pass
through the electrical grounding path, and to pass from the
metallic rib post through the spar to the CRN cable.
4. The composite rib of claim 1, wherein the metallic grounding
member is a non-structural member.
5. The composite rib of claim 1, wherein the metallic fitting is a
first metallic fitting, the skin panel is an upper skin panel, and
the electrical grounding path is a first electrical grounding path,
wherein the composite rib further comprises a second metallic
fitting coupled to the CFRP panel and configured to be coupled to a
lower skin panel of the aircraft wing, and wherein the metallic
grounding member is further positioned between the CFRP panel and
the second metallic fitting, the metallic grounding member
providing a second electrical grounding path extending from the
second metallic fitting to the metallic rib post.
6. The composite rib of claim 5, wherein the metallic grounding
member is a metallic grounding plate.
7. The composite rib of claim 6, wherein the metallic grounding
plate includes a border and an opening surrounded by the border,
the opening being located between the first and second metallic
fittings, the first and second metallic fittings contacting the
border, the border connecting the first and second electrical
grounding paths.
8. The composite rib of claim 6, wherein the metallic grounding
plate includes a first surface and a second surface located
opposite the first surface, the first surface contacting the CFRP
panel, the second surface contacting the first and second metallic
fittings.
9. The composite rib of claim 6, further comprising a hat stiffener
coupled to the CFRP panel.
10. The composite rib of claim 6, wherein the first metallic
fitting is a first upper metallic fitting and the second metallic
fitting is a first lower metallic fitting, the composite rib
further comprising: a second upper metallic fitting coupled to the
CFRP panel and configured to be coupled to the upper skin panel,
the second upper metallic fitting being spaced apart from the first
upper metallic fitting; a second lower metallic fitting coupled to
the CFRP panel and configured to be coupled to the lower skin
panel, the second lower metallic fitting being spaced apart from
the first lower metallic fitting; a first shear tie coupled to the
metallic grounding plate at a location between the first and second
upper metallic fittings; and a second shear tie coupled to the
metallic grounding plate at a location between the first and second
lower metallic fittings.
11. The composite rib of claim 9, wherein the CFRP panel includes a
first surface and a second surface located opposite the first
surface, the hat stiffener contacting the first surface of the CFRP
panel, the metallic grounding plate contacting the second surface
of the CFRP panel.
12. The composite rib of claim 11, wherein the hat stiffener is
bonded to the first surface of the CFRP panel, and the metallic
grounding plate is bonded to the second surface of the CFRP
panel.
13. The composite rib of claim 11, wherein the CFRP panel further
includes a central segment defining a plane, a first flange
extending away from the central segment at a first angle relative
to the plane, and a second flange extending away from the central
segment at a second angle relative to the plane, and wherein the
hat stiffener is located between the first flange and the second
flange.
14. The composite rib of claim 11, further comprising: a first
fastener extending through the first metallic fitting, the metallic
grounding plate, the CFRP panel, and the hat stiffener; and a
second fastener extending through the second metallic fitting, the
metallic grounding plate, the CFRP panel, and the hat
stiffener.
15. A method for assembling a composite rib, the method comprising:
coupling a metallic grounding member to a carbon fiber reinforced
plastic (CFRP) panel; coupling a metallic rib post to the CFRP
panel, the metallic rib post configured to be coupled to a spar of
an aircraft wing, the spar coupled to a current return network
(CRN) cable; and coupling a metallic fitting to the CFRP panel, the
metallic fitting configured to be coupled to a skin panel of the
aircraft wing; wherein the metallic grounding member is positioned
between the CFRP panel and the metallic fitting, the metallic
grounding member providing an electrical grounding path extending
from the metallic fitting to the metallic rib post.
16. The method of claim 15, wherein the metallic fitting is a first
metallic fitting, the skin panel is an upper skin panel, and the
electrical grounding path is a first electrical grounding path,
wherein the method further comprises coupling a second metallic
fitting to the CFRP panel, the second metallic fitting configured
to be coupled to a lower skin panel of the aircraft wing, and
wherein the metallic grounding member is further positioned between
the CFRP panel and the second metallic fitting, the metallic
grounding member providing a second electrical grounding path
extending from the second metallic fitting to the metallic rib
post.
17. The method of claim 16, wherein the metallic grounding member
is a metallic grounding plate.
18. The method of claim 17, wherein the metallic grounding plate
includes a border and an opening surrounded by the border, the
opening being located between the first and second metallic
fittings, the first and second metallic fittings contacting the
border, the border connecting the first and second electrical
grounding paths.
19. The method of claim 17, further comprising coupling a hat
stiffener to the CFRP panel.
20. The method of claim 19, wherein the CFRP panel includes a first
surface and a second surface located opposite the first surface,
the hat stiffener contacting the first surface of the CFRP panel,
the metallic grounding plate contacting the second surface of the
CFRP panel.
21. The method of claim 20, wherein the coupling the hat stiffener
to the CFRP panel includes bonding the hat stiffener to the first
surface of the CFRP panel, and wherein the coupling the metallic
grounding plate to the CFRP panel includes bonding the metallic
grounding plate to the second surface of the CFRP panel.
22. The method of claim 20, wherein the coupling the first metallic
fitting to the CFRP panel includes extending a first fastener
through the first metallic fitting, the metallic grounding plate,
the CFRP panel, and the hat stiffener, and wherein the coupling the
second metallic fitting to the CFRP panel includes extending a
second fastener through the second metallic fitting, the metallic
grounding plate, the CFRP panel, and the hat stiffener.
Description
FIELD OF THE DISCLOSURE
This disclosure relates generally to composite ribs for aircraft
wings and, more specifically, to aircraft wing composite ribs
having electrical grounding paths.
BACKGROUND
Ribs are commonly implemented within aircraft wings (e.g., between
upper and lower skin panels of the aircraft wing, and between front
and rear spars of the aircraft wing) as structural, load-bearing
devices configured to provide tensile and/or compressive support to
enhance the overall structural integrity of the aircraft wings.
Known ribs include a metallic panel that is configured to be
vertically oriented between the upper and lower skin panels of the
aircraft wing, a first metallic rib post configured to couple the
metallic panel to the front spar of the aircraft wing, a second
metallic rib post configured to couple the metallic panel to the
rear spar of the aircraft wing, first (e.g., upper) metallic
fittings configured to couple the metallic panel to the upper skin
panel of the aircraft wing, and second (e.g., lower) metallic
fittings configured to couple the metallic panel to the lower skin
panel of the aircraft wing. Current return network (CRN) cables can
be coupled to the front and rear spars to facilitate carrying
and/or dissipating electrical current and/or electrostatic charge
away from the ribs and into the atmosphere.
The metallic (e.g., aluminum) components of the above-described
known ribs typically have a buy-to-fly ratio and/or weight that
is/are elevated relative to the buy-to-fly ratio and/or weight of
non-metallic structural materials such as carbon fiber reinforced
plastic (CFRP) that could alternatively be used to construct such
components of the rib. Modifying the construction of known ribs to
include a CFRP panel in lieu of a metallic panel can advantageously
provide a rib having a relatively lower buy-to-fly ratio and/or
weight.
SUMMARY
Example aircraft wing composite ribs having electrical grounding
paths are disclosed herein. In some examples, a composite rib is
disclosed. In some disclosed examples, the composite rib comprises
a CFRP panel. In some disclosed examples, the composite rib further
comprises a metallic rib post coupled to the CFRP panel and
configured to be coupled to a spar of an aircraft wing. In some
disclosed examples, the spar is coupled to a CRN cable. In some
disclosed examples, the composite rib further comprises a metallic
fitting coupled to the CFRP panel and configured to be coupled to a
skin panel of the aircraft wing. In some disclosed examples, the
composite rib further comprises a metallic grounding member
positioned between the CFRP panel and the metallic fitting. In some
disclosed examples, the metallic grounding member provides an
electrical grounding path extending from the metallic fitting to
the metallic rib post.
In some examples, a method for assembling a composite rib is
disclosed. In some disclosed examples, the method comprises
coupling a metallic grounding member to a CFRP panel. In some
disclosed examples, the method further comprises coupling a
metallic rib post to the CFRP panel. In some disclosed examples,
the metallic rib post is configured to be coupled to a spar of an
aircraft wing. In some disclosed examples, the spar is coupled to a
CRN cable. In some disclosed examples, the method further comprises
coupling a metallic fitting to the CFRP panel. In some disclosed
examples, the metallic fitting is configured to be coupled to a
skin panel of the aircraft wing. In some disclosed examples of the
method, the metallic grounding member is positioned between the
CFRP panel and the metallic fitting, and the metallic grounding
member provides an electrical grounding path extending from the
metallic fitting to the metallic rib post.
Example metallic fittings or coupling composite ribs to skin panels
of aircraft wings are also disclosed herein. In some examples, a
metallic fitting configured to couple a composite rib to a skin
panel of an aircraft wing is disclosed. In some disclosed examples,
the metallic fitting comprises a through hole configured to receive
a fastener. In some disclosed examples, the fastener is configured
to couple the metallic fitting to the composite rib. In some
disclosed examples, the metallic fitting further comprises a bore
configured to receive a bolt. In some disclosed examples, the
metallic fitting further comprises a cavity intersecting the bore.
In some disclosed examples, the cavity has an access opening. In
some disclosed examples, the metallic fitting further comprises a
barrel nut located within the cavity. In some disclosed examples,
the barrel nut is configured to threadably engage the bolt to
couple the metallic fitting to the skin panel. In some disclosed
examples, the metallic fitting further comprises a seal located
within the cavity. In some disclosed examples, the seal is
configured to close the access opening.
In some examples, a method for coupling a composite rib to a skin
panel of an aircraft wing via a metallic fitting is disclosed. In
some disclosed examples, the method comprises extending a fastener
through a through hole of the metallic fitting to couple the
metallic fitting to the composite rib. In some disclosed examples,
the method further comprises extending a bolt into a bore of the
metallic fitting to couple the metallic fitting to the skin panel.
In some disclosed examples, the bolt threadably engages a barrel
nut located within a cavity of the metallic fitting. In some
disclosed examples, the cavity intersects the bore and has an
access opening. In some disclosed examples, the access opening is
closed by a seal located within the cavity.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of an example composite rib constructed
in accordance with teachings of this disclosure.
FIG. 2 is a perspective view of the example composite rib of FIG. 1
in an assembled state.
FIG. 3 is a perspective view of the example composite rib of FIGS.
1 and 2 in an assembled state and coupled to example spars of an
example aircraft wing.
FIG. 4 is a cross-sectional view of the example composite rib of
FIGS. 1-3 in an assembled state and coupled to example skin panels
of the aircraft wing of FIG. 3.
FIG. 5 is a perspective view of one of the example first metallic
fittings of the example composite rib of FIGS. 1-4.
FIG. 6 is an exploded view of an example alternate composite rib
constructed in accordance with teachings of this disclosure.
FIG. 7 is a perspective view of the example alternate composite rib
of FIG. 6 in an assembled state.
Certain examples are shown in the above-identified figures and
described in detail below. In describing these examples, like or
identical reference numbers are used to identify the same or
similar elements. The figures are not necessarily to scale and
certain features and certain views of the figures may be shown
exaggerated in scale or in schematic for clarity and/or
conciseness.
DETAILED DESCRIPTION
As used herein in the context of describing a member, part or
component of an apparatus, the term "structural" means that the
member, part or component is a load-bearing member, part or
component that is essential to the stability of the apparatus. For
example, a structural component of a composite rib of an aircraft
wing is a load-bearing component that is essential to the stability
of the composite rib and/or the aircraft wing. Conversely, as used
herein in the context of describing a member, part or component of
an apparatus, the term "non-structural" means that the member, part
or component is a non-load-bearing member, part or component that
is not essential to the stability of the apparatus. For example, a
non-structural component of a composite rib of an aircraft wing is
a non-load-bearing component that is not essential to the stability
of the composite rib and/or the aircraft wing.
Known ribs include a metallic panel that is configured to be
vertically oriented between the upper and lower skin panels of the
aircraft wing, a first metallic rib post configured to couple the
metallic panel to a front spar of the aircraft wing, a second
metallic rib post configured to couple the metallic panel to a rear
spar of the aircraft wing, first (e.g., upper) metallic fittings
configured to couple the metallic panel to the upper skin panel of
the aircraft wing, and second (e.g., lower) metallic fittings
configured to couple the metallic panel to the lower skin panel of
the aircraft wing. The metallic (e.g., aluminum) components of such
ribs typically have a buy-to-fly ratio and/or weight that is/are
elevated relative to the buy-to-fly ratio and/or weight of
non-metallic structural materials such as CFRP that could
alternatively be used to construct such components of the rib.
Modifying the construction of known ribs to include a CFRP panel in
lieu of a metallic panel can advantageously provide a rib having a
relatively lower buy-to-fly ratio and/or weight.
Implementing a rib having a CFRP panel instead of a metallic panel
can also advantageously reduce thermally-induced fatigue loading of
the rib. For example, the coefficient of thermal expansion for CFRP
is significantly lower than the coefficient of thermal expansion
for aluminum. When the rib includes an aluminum panel, first (e.g.,
upper) aluminum fittings, and second (e.g., lower) aluminum
fittings, thermal shrinkage of the aluminum panel causes tension
relative to the first and/or second aluminum fittings. Replacing
the aluminum panel of the rib with a CFRP panel produces a
difference and/or mismatch in the coefficient of thermal expansion
between the CFRP panel and the first and second aluminum fittings,
thereby advantageously reducing the aforementioned tension that
would otherwise exist relative to the first and/or second aluminum
fittings.
While implementing a composite rib having a CFRP panel can provide
the advantages described above, implementing the CFRP panel in lieu
of a corresponding metallic panel can result in drawbacks with
regard to lightning strike protection and/or dissipating
electrostatic charge. For example, because CFRP is not a highly
conductive material, implementing a composite rib having a CFRP
panel in lieu of a corresponding metallic (e.g., aluminum) panel
can break (e.g., eliminate) one or more electrical grounding
path(s) that, in the presence of the metallic panel, would
otherwise extend from the first (e.g., upper) metallic fittings
(e.g., coupled to the upper skin panel of the aircraft) to the
first metallic rib post (e.g., coupled to the front spar of the
aircraft) and/or the second metallic rib post (e.g., coupled to the
rear spar of the aircraft), and/or from the second (e.g., lower)
metallic fittings (e.g., coupled to the lower skin panel of the
aircraft) to the first metallic rib post (e.g., coupled to the
front spar of the aircraft) and/or the second metallic rib post
(e.g., coupled to the rear spar of the aircraft). Breaking the
aforementioned electrical grounding path(s) prevents electrical
current and/or electrostatic charge from passing to the CRN
cable(s) coupled to the front and rear spars, and accordingly
inhibits carrying and/or dissipating such electrical current and/or
electrostatic charge away from the composite rib.
Example aircraft wing composite ribs disclosed herein
advantageously include a CFRP panel, a metallic rib post, a
metallic fitting, and a metallic grounding member (e.g., a metallic
grounding plate or a metallic grounding cable). The metallic rib
post is coupled to the CFRP panel and is configured to be coupled
to a spar of an aircraft wing, the spar being coupled to a CRN
cable. The metallic fitting is coupled to the CFRP panel and is
configured to be coupled to a skin panel of the aircraft wing. The
metallic grounding member is positioned between the CFRP panel and
the metallic fitting, thereby advantageously providing an
electrical grounding path that extends from the metallic fitting to
the metallic rib post. The electrical grounding path enables
electrical current and/or electrostatic charge to pass from the
metallic fitting to the metallic rib post. The electrical current
and/or electrostatic charge can thereafter pass from the metallic
rib post through the spar to the CRN cable, thereby allowing for
such electrical current and/or electrostatic charge to be carried
and/or dissipated away from the composite rib and into the
atmosphere. The electrical grounding path formed by the metallic
grounding member of the example aircraft wing composite ribs
disclosed herein provides enhanced and/or improved lightning strike
protection without compromising and/or impeding the above-described
benefits associated with implementing a composite rib having a CFRP
panel in lieu of a corresponding metallic (e.g., aluminum)
panel.
FIG. 1 is an exploded view of an example composite rib 100
constructed in accordance with teachings of this disclosure. FIG. 2
is a perspective view of the example composite rib 100 of FIG. 1 in
an assembled state. FIG. 3 is a perspective view of the example
composite rib of FIGS. 1 and 2 in an assembled state and coupled to
example spars of an example aircraft wing 300. FIG. 4 is a
cross-sectional view of the example composite rib 100 of FIGS. 1-3
in an assembled state and coupled to example skin panels of the
aircraft wing 300 of FIG. 3. As shown in FIGS. 3 and 4, the
aircraft wing 300 includes an example front spar 302, an example
rear spar 304, an example first (e.g., upper) skin panel 402, and
an example second (e.g., lower) skin panel 404. The composite rib
100 of FIGS. 1-4 is configured to be coupled to the front and rear
spars 302, 304 and to the upper and lower skin panels 402, 404 of
the aircraft wing 300.
In the illustrated example of FIGS. 1-4, the composite rib 100
includes an example CFRP panel 102, example hat stiffeners 104, an
example metallic grounding member and/or metallic grounding plate
106, an example first (e.g., upper) metallic fittings 108, example
second (e.g., lower) metallic fittings 110, example first (e.g.,
upper) fasteners 112, and example second (e.g., lower) fasteners
114. As shown in FIG. 3, the composite rib 100 of FIGS. 1-4 further
includes an example first metallic rib post 306 configured to
couple the composite rib 100 to the front spar 302 of the aircraft
wing 300, and an example second metallic rib post 308 configured to
couple the composite rib 100 to the rear spar 304 of the aircraft
wing 300.
As shown in FIG. 1, the composite rib 100 of FIGS. 1-4 includes
three (3) hat stiffeners 104, three (3) first metallic fittings
108, three (3) second metallic fittings 110, twelve (12) first
fasteners 112, and twelve (12) second fasteners 114. In other
examples, the number of hat stiffeners 104, first metallic fittings
108, second metallic fittings 110, first fasteners 112, and/or
second fasteners 114 can differ from that shown in FIG. 1. For
example, the composite rib 100 can include any number (e.g., 1, 2,
4, 6, 12, etc.) of hat stiffeners 104, any number (e.g., 1, 2, 4,
6, 12, etc.) of first metallic fittings 108, any number (e.g., 1,
2, 4, 6, 12, etc.) of second metallic fittings 110, any number
(e.g., 1, 2, 3, 6, 9, 24, etc.) of first fasteners 112, and/or any
number (e.g., 1, 2, 3, 6, 9, 24, etc.) of second fasteners 114.
In the illustrated example of FIGS. 1-4, the number of hat
stiffeners 104, the number of first metallic fittings 108, and the
number of second metallic fittings 110 are all equal to one
another. In other examples, the number of hat stiffeners 104, the
number of first metallic fittings 108, and/or the number of second
metallic fittings 110 can differ from one another. In the
illustrated example of FIGS. 1-4, the number of first fasteners 112
is equal to the number of second fasteners 114, each of the first
metallic fittings 108 is configured to receive the same number
(e.g., four) of the first fasteners 112, and each of the second
metallic fittings is configured to receive the same number (e.g.,
four) of the second fasteners 114. In other examples, the number of
first fasteners 112 can differ from the number of second fasteners
114, respective ones of the first metallic fittings 108 can be
configured to receive a different number of the first fasteners 112
relative to one another, and/or respective ones of the second
metallic fittings can be configured to receive a different number
of the second fasteners 114 relative to one another.
The CFRP panel 102 of FIGS. 1-4 is a structural and/or load-bearing
member of the composite rib 100. In the illustrated example of
FIGS. 1-4, the CFRP panel 102 includes an example first surface
116, an example second surface 118 located opposite the first
surface 116 of the CFRP panel 102, an example first end 120, an
example second end 122 located opposite the first end 120 of the
CFRP panel 102, a third (e.g., upper) surface 124 extending between
the first and second ends 120, 122 of the CFRP panel 102, and a
fourth (e.g., lower) surface 126 extending between the first and
second ends 120, 122 of the CFRP panel 102 and located opposite the
third surface 124 of the CFRP panel 102. In some examples, the
first surface 116 of the CFRP panel 102 is an inboard-facing
surface (e.g., facing and/or oriented toward a fuselage of the
aircraft), and the second surface 118 of the CFRP panel 102 is an
outboard-facing surface (e.g., facing and/or oriented away from the
fuselage of the aircraft). In other examples, the first surface 116
of the CFRP panel 102 can be an outboard-facing surface, and the
second surface 118 of the CFRP panel 102 can be an inboard-facing
surface. In some examples, the first end 120 of the CFRP panel 102
is a forward-facing end (e.g., facing and/or oriented toward a
front spar and/or a leading edge of the wing of the aircraft), and
the second end 122 of the CFRP panel 102 is a rearward-facing end
(e.g., facing and/or oriented toward a rear spar and/or a trailing
edge of the wing of the aircraft). In other examples, the first end
120 of the CFRP panel 102 can be a rearward-facing end, and the
second end 122 of the CFRP panel 102 can be a forward-facing
end.
In the illustrated example of FIGS. 1-4, the third surface 124 of
the CFRP panel 102 is an upper and/or upward-facing surface
configured to be oriented toward an example upper skin panel 402 of
the aircraft wing 300, and the fourth surface 126 of the CFRP panel
102 is a lower and/or downward-facing surface configured to be
oriented toward an example lower skin panel 404 of the aircraft
wing 300. As shown in FIGS. 1-4, the third surface 124 of the CFRP
panel 102 has a concave downward curvature between the first and
second ends 120, 122 of the CFRP panel 102, and the fourth surface
126 of the CFRP panel 102 has a concave upward curvature between
the first and second ends 120, 122 of the CFRP panel 102. In some
examples, the concave downward curvature of the third surface 124
of the CFRP panel 102 can track, match and/or be complementary to a
corresponding concave downward curvature of the upper skin panel
402 of the aircraft wing 300, and the concave upward curvature of
the fourth surface 126 of the CFRP panel 102 can track, match
and/or be complementary to a corresponding concave upward curvature
of the lower skin panel 404 of the aircraft wing 300. In other
examples, the third surface 124 and/or the fourth surface 126 of
the CFRP panel 102 can have a curvature which differs from that
shown in FIGS. 1-4. In some examples, the third surface 124 and/or
the fourth surface 126 of the CFRP panel 102 can be a linear
surface.
The CFRP panel 102 of FIGS. 1-4 further includes an example central
segment 128, an example first flange 130, and an example second
flange 132. In the illustrated example of FIGS. 1-4, the boundaries
of the central segment 128 of the CFRP panel 102 are formed and/or
defined by the first and second ends 120, 122 and the third and
fourth surfaces 124, 126 of the CFRP panel 102. The central segment
128 of the CFRP panel 102 defines an example plane 134 that extends
and/or is oriented vertically between the upper and lower skin
panels 402, 404 of the aircraft wing 300 when the composite rib 100
is coupled to the aircraft wing 300. As shown in FIGS. 1-4, the
first flange 130 of the CFRP panel 102 is formed along and/or
proximate to the third surface 124 of the CFRP panel 102, and the
second flange 132 of the CFRP panel 102 is formed along and/or
proximate to the fourth surface 126 of the CFRP panel 102.
In the illustrated example of FIGS. 1-4, the first and second
flanges 130, 132 of the CFRP panel 102 are respectively formed as
continuous members extending between the first and second ends 120,
122 of the CFRP panel 102. In other examples, the first flange 130
and/or the second flange 132 of the CFRP panel 102 can
alternatively be implemented as multiple flanges that are separated
and/or spaced-apart from one another. For example, the first flange
130 of the CFRP panel 102 can be implemented as multiple flanges
that are spaced apart from one another and formed along and/or
proximate to the third surface 124 of the CFRP panel 102. As
another example, the second flange 132 of the CFRP panel 102 can be
implemented as multiple flanges that are spaced apart from one
another and formed along and/or proximate to the fourth surface 126
of the CFRP panel 102. In still other examples, the first flanges
130 and/or the second flanges 132 can be omitted from the CFRP
panel 102.
The first flange 130 of the CFRP panel 102 of FIGS. 1-4 extends
away from the central segment 128 of the CFRP panel 102 at an
example first angle 136 relative to the plane 134 of the central
segment 128, and the second flange 132 of the CFRP panel 102 of
FIGS. 1-4 extends away from the central segment 128 of the CFRP
panel 102 at an example second angle 138 relative to the plane 134
of the central segment 128. In the illustrated example of FIGS.
1-4, the first and second angles 136, 138 are each approximately
equal to ninety degrees. In other examples, the first angle 136
and/or the second angle 138 can be a value greater than or less
than ninety degrees (e.g., eighty degrees, one hundred degrees,
etc.).
The CFRP panel 102 of FIGS. 1-4 further includes example first
(e.g., upper) through holes 140 extending from the first surface
116 of the CFRP panel 102 through to the second surface 118 of the
CFRP panel 102, as well as example second (e.g., lower) through
holes 142 also extending from the first surface 116 of the CFRP
panel 102 through to the second surface 118 of the CFRP panel 102.
As further described below, the first (e.g., upper) through holes
140 of the CFRP panel 102 are configured to receive corresponding
ones of the first (e.g., upper) fasteners 112 to facilitate
coupling the hat stiffeners 104, the metallic grounding plate 106,
and/or the first (e.g., upper) metallic fittings 108 to the CFRP
panel 102 of the composite rib 100. Similarly, the second (e.g.,
lower) through holes 142 of the CFRP panel 102 are configured to
receive corresponding ones of the second (e.g., lower) fasteners
114 to facilitate coupling the hat stiffeners 104, the metallic
grounding plate 106, and/or the second (e.g., lower) metallic
fittings 110 to the CFRP panel 102 of the composite rib 100.
The CFRP panel 102 can include any number of first (e.g., upper)
through holes 140 configured, positioned and/or oriented to receive
any corresponding number of first (e.g., upper) fasteners 112,
and/or to align with any corresponding number of through holes
formed respectively in the hat stiffeners 104, the metallic
grounding plate 106, and/or the first metallic fittings 108 of the
composite rib 100. Similarly, the CFRP panel 102 can include any
number of second (e.g., lower) through holes 142 configured,
positioned and/or oriented to receive any corresponding number of
second (e.g., lower) fasteners 114, and/or to align with any
corresponding number of through holes formed respectively in the
hat stiffeners 104, the metallic grounding plate 106, and/or the
second metallic fittings 110 of the composite rib 100.
The hat stiffeners 104 of FIGS. 1-4 are structural and/or
load-bearing members of the composite rib 100. In some examples,
the hat stiffeners 104 can be CFRP hat stiffeners, and can
accordingly be made from the same material as the CFRP panel 102 of
the composite rib 100. In other examples, one or more of the hat
stiffeners 104 can alternatively be made from a material other than
CFRP including, for example, a different plastic material and/or a
metal material. In the illustrated example of FIGS. 1-4, each one
of the hat stiffeners 104 includes an example first (e.g., upper)
end 144, and an example second (e.g., lower) end 146 located
opposite the first end 144 of the hat stiffener 104, a pair of
example flanges 148 extending between the first and second ends
144, 146 of the hat stiffener 104, and an example hat portion 150
extending between the first and second ends 144, 146 of the hat
stiffener 104 and bridging and extending away from the flanges 148
of the hat stiffener 104. In the illustrated example of FIGS. 1-4,
the first end 144 of each hat stiffener 104 is an upper and/or
upward-facing end configured to be oriented toward the upper skin
panel 402 of the aircraft wing 300, and the second end 146 of each
hat stiffener 104 is a lower and/or downward-facing end configured
to be oriented toward the lower skin panel 404 of the aircraft wing
300.
The flanges 148 of each hat stiffener 104 of FIGS. 1-4 include
example first (e.g., upper) through holes 152 extending through the
flanges 148 of the hat stiffener 104, as well as example second
(e.g., lower) through holes 154 extending through the flanges 148
of the hat stiffener 104. As further described below, the first
(e.g., upper) through holes 152 of each hat stiffener 104 are
configured to receive corresponding ones of the first (e.g., upper)
fasteners 112 to facilitate coupling the hat stiffener 104 to the
CFRP panel 102 of the composite rib 100. Similarly, the second
(e.g., lower) through holes 154 of each hat stiffener 104 are
configured to receive corresponding ones of the second (e.g.,
lower) fasteners 114 to facilitate coupling the hat stiffener 104
to the CFRP panel 102 of the composite rib 100.
The hat stiffeners 104 can include any number of first (e.g.,
upper) through holes 152 configured, positioned and/or oriented to
receive any corresponding number of first (e.g., upper) fasteners
112, and/or to align with any corresponding number of through holes
formed respectively in the CFRP panel 102, the metallic grounding
plate 106, and/or the first metallic fittings 108 of the composite
rib 100. Similarly, the hat stiffeners 104 can include any number
of second (e.g., lower) through holes 154 configured, positioned
and/or oriented to receive any corresponding number of second
(e.g., lower) fasteners 114, and/or to align with any corresponding
number of through holes formed respectively in the CFRP panel 102,
the metallic grounding plate 106, and/or the second metallic
fittings 110 of the composite rib 100.
When the composite rib 100 of FIGS. 1-4 is in an assembled state
(e.g., as shown in FIGS. 2-4), the hat stiffeners 104 are coupled
to the CFRP panel 102. In some examples, the hat stiffeners 104 are
coupled to the CFRP panel 102 by bonding the flanges 148 of the hat
stiffeners 104 to the first surface 116 of the CFRP panel 102. In
some examples, the hat stiffeners 104 are additionally or
alternatively coupled to the CFRP panel 102 by extending one or
more of the first (e.g., upper) fastener(s) 112 through a
corresponding one or more of the first (e.g., upper) through
hole(s) 140 of the CFRP panel 102 and through a corresponding one
or more of the first (e.g., upper) through hole(s) 152 of the hat
stiffeners 104, and/or by extending one or more of the second
(e.g., lower) fastener(s) 114 through a corresponding one or more
of the second (e.g., lower) through hole(s) 142 of the CFRP panel
102 and through a corresponding one or more of the second (e.g.,
lower) through hole(s) 154 of the hat stiffeners 104.
In the illustrated example of FIGS. 2-4, the flanges 148 of each
one of the hat stiffeners 104 contact the first surface 116 of the
CFRP panel 102. Each one of the hat stiffeners 104 is positioned
along the first surface 116 of the CFRP panel 102 such that the
first end 144 of the hat stiffener 104 faces and/or is oriented
toward the third surface 124 and/or the first flange 130 of the
CFRP panel 102, and the second end 146 of the hat stiffener 104
faces and/or is oriented toward the fourth surface 126 and/or the
second flange 132 of the CFRP panel 102. Each one of the hat
stiffeners 104 is accordingly located between the third and fourth
surfaces 124, 126 of the CFRP panel 102, and/or between the first
and second flanges 130, 132 of the CFRP panel 102.
The metallic grounding plate 106 of FIGS. 1-4 is a non-structural
and/or non-load-bearing member of the composite rib 100. In some
examples, the metallic grounding plate 106 can be made from
aluminum, which is a highly conductive metal. In other examples,
the metallic grounding plate 106 can alternatively be made from a
metal material other than aluminum including, for example, another
highly conductive metal such as copper or nickel. In the
illustrated example of FIGS. 1-4, the metallic grounding plate 106
includes an example first surface 156, an example second surface
158 located opposite the first surface 156 of the metallic
grounding plate 106, an example first end 160, an example second
end 162 located opposite the first end 160 of the metallic
grounding plate 106, a third (e.g., upper) surface 164 extending
between the first and second ends 160, 162 of the metallic
grounding plate 106, and a fourth (e.g., lower) surface 166
extending between the first and second ends 160, 162 of the
metallic grounding plate 106 and located opposite the third surface
164 of the metallic grounding plate 106. The first surface 156 of
the metallic grounding plate 106 faces and/or is oriented toward
the second surface 118 of the CFRP panel 102. The second surface
158 of the metallic grounding plate 106 faces and/or is oriented
away from the second surface of the CFRP panel 102 and toward the
first and second metallic fittings 108, 110. The first end 160 of
the metallic grounding plate 106 faces and/or is oriented toward
the first end 120 of the CFRP panel 102, and the second end 162 of
the metallic grounding plate 106 faces and/or is oriented toward
the second end 122 of the CFRP panel 102.
The third surface 164 of the metallic grounding plate 106 faces
and/or is oriented toward the third surface 124 of the CFRP panel
102, and the fourth surface 166 of the metallic grounding plate 106
faces and/or is oriented toward the fourth surface 126 of the CFRP
panel 102. As shown in FIGS. 1-4, the third surface 164 of the
metallic grounding plate 106 has a concave downward curvature
between the first and second ends 160, 162 of the metallic
grounding plate 106, and the fourth surface 166 of the metallic
grounding plate 106 has a concave upward curvature between the
first and second ends 160, 162 of the metallic grounding plate 106.
In the illustrated example of FIGS. 1-4, the concave downward
curvature of the third surface 164 of the metallic grounding plate
106 tracks, matches and/or is complementary to the concave downward
curvature of the third surface 124 of the CFRP panel 102, and the
concave upward curvature of the fourth surface 166 of the metallic
grounding plate 106 tracks, matches and/or is complementary to the
concave upward curvature of the fourth surface 126 of the CFRP
panel 102. In other examples, the third surface 164 and/or the
fourth surface 166 of the metallic grounding plate 106 can have a
curvature which differs from that shown in FIGS. 1-4. In some
examples, the third surface 164 and/or the fourth surface 166 of
the metallic grounding plate 106 can be a linear surface.
The metallic grounding plate 106 of FIGS. 1-4 further includes an
example border 168 and an example opening 170. In the illustrated
example of FIGS. 1-4, the border 168 of the metallic grounding
plate 106 surrounds the opening 170 of the metallic grounding plate
106. The outer boundaries of the border 168 of the metallic
grounding plate 106 are formed and/or defined by the first and
second ends 160, 162 and the third and fourth surfaces 164, 166 of
the metallic grounding plate 106. The inner boundaries of the
border 168 of the metallic grounding plate 106 are formed and/or
defined by the opening 170. The opening 170 of the metallic
grounding plate 106 extends from the first surface 156 of the
metallic grounding plate 106 through to the second surface 158 of
the metallic grounding plate 106. The presence of the opening 170
reduces the overall weight of the metallic grounding plate 106
relative to an alternative implementation of the metallic grounding
plate 106 that lacks the opening 170. In the illustrated example of
FIGS. 1-4, the opening 170 of the metallic grounding plate 106 is
located between the first metallic fittings 108 and the second
metallic fittings 110 of the composite rib 100.
As further described below in connection with FIG. 3, the border
168 and/or, more generally, the metallic grounding plate 106
provides a first electrical grounding path extending from the first
metallic fittings 108 of the composite rib 100 to one or more
example metallic rib posts of the composite rib 100, and further
provides a second electrical grounding path extending from the
second metallic fittings 110 of the composite rib 100 to the one or
more metallic rib posts of the composite rib 100. As further
described below in connection with FIG. 3, the border 168 and/or,
more generally, the metallic grounding plate 106 connects the first
electrical grounding path to the second electrical grounding
path.
In the illustrated example of FIGS. 1-4, the border 168 of the
metallic grounding plate 106 has an elongated annular shape
extending between the first and second ends 160, 162 and the third
and fourth surfaces 164, 166 of the metallic grounding plate 106.
In other examples, the border 168 and/or, more generally, the
metallic grounding plate 106 can be implemented in a different
manner that nonetheless provides one or more electrical grounding
path(s) extending from the first and/or second metallic fittings
108, 110 of the composite rib 100 to one or more metallic rib posts
of the composite rib 100. For example, the border 168 and/or, more
generally, the metallic grounding plate 106 can be constructed in a
manner that omits the opening 170 from the metallic grounding plate
106. As another example, the border 168 and/or, more generally, the
metallic grounding plate 106 can be constructed in a manner that
provides multiple (e.g., 2, 3, 10, 50, etc.) openings in lieu of
the single opening 170 shown in FIGS. 1-4. As another example, the
border 168 and/or, more generally, the metallic grounding plate 106
can be constructed to have a non-annular shape. The border 168
and/or, more generally, the metallic grounding plate 106 can be
constructed to have any shape (e.g., any regular or irregular
shape) and/or any pattern (e.g., any regular or irregular pattern)
that provides one or more electrical grounding path(s) extending
from the first and/or second metallic fittings 108, 110 of the
composite rib 100 to one or more metallic rib posts of the
composite rib 100.
The metallic grounding plate 106 of FIGS. 1-4 further includes
example first (e.g., upper) through holes 172 extending from the
first surface 156 of the metallic grounding plate 106 through to
the second surface 158 of the metallic grounding plate 106, as well
as example second (e.g., lower) through holes 174 also extending
from the first surface 156 of the metallic grounding plate 106
through to the second surface 158 of the metallic grounding plate
106. As further described below, the first (e.g., upper) through
holes 172 of the metallic grounding plate 106 are configured to
receive corresponding ones of the first (e.g., upper) fasteners 112
to facilitate coupling the metallic grounding plate 106 and/or the
first (e.g., upper) metallic fittings 108 to the CFRP panel 102 of
the composite rib 100. Similarly, the second (e.g., lower) through
holes 174 of the metallic grounding plate 106 are configured to
receive corresponding ones of the second (e.g., lower) fasteners
114 to facilitate coupling the metallic grounding plate 106 and/or
the second (e.g., lower) metallic fittings 110 to the CFRP panel
102 of the composite rib 100.
The metallic grounding plate 106 can include any number of first
(e.g., upper) through holes 172 configured, positioned and/or
oriented to receive any corresponding number of first (e.g., upper)
fasteners 112, and/or to align with any corresponding number of
through holes formed respectively in the CFRP panel 102, the hat
stiffeners 104, and/or the first metallic fittings 108 of the
composite rib 100. Similarly, the metallic grounding plate 106 can
include any number of second (e.g., lower) through holes 174
configured, positioned and/or oriented to receive any corresponding
number of second (e.g., lower) fasteners 114, and/or to align with
any corresponding number of through holes formed respectively in
the CFRP panel 102, the hat stiffeners 104, and/or the second
metallic fittings 110 of the composite rib 100.
When the composite rib 100 of FIGS. 1-4 is in an assembled state
(e.g., as shown in FIGS. 2-4), the metallic grounding plate 106 is
coupled to the CFRP panel 102. In some examples, the metallic
grounding plate 106 is coupled to the CFRP panel 102 by bonding the
first surface 156 of the metallic grounding plate 106 to the second
surface 118 of the CFRP panel 102. In some examples, the metallic
grounding plate 106 is additionally or alternatively coupled to the
CFRP panel 102 by extending one or more of the first (e.g., upper)
fastener(s) 112 through a corresponding one or more of the first
(e.g., upper) through hole(s) 172 of the metallic grounding plate
106 and through a corresponding one or more of the first (e.g.,
upper) through hole(s) 140 of the CFRP panel 102, and/or by
extending one or more of the second (e.g., lower) fastener(s) 114
through a corresponding one or more of the second (e.g., lower)
through hole(s) 174 of the metallic grounding plate 106 and through
a corresponding one or more of the second (e.g., lower) through
hole(s) 142 of the CFRP panel 102.
In the illustrated example of FIGS. 2-4, the metallic grounding
plate 106 is positioned and/or located between the CFRP panel 102
and the first and second metallic fittings 108, 110. The first
surface 156 of the metallic grounding plate 106 contacts the second
surface 118 of the CFRP panel 102. The first metallic fittings 108
and the second metallic fittings 110 are respectively positioned,
located, and/or arranged about the border 168 of the metallic
grounding plate 106. The second surface 158 of the metallic
grounding plate 106 contacts each of the first (e.g., upper)
metallic fittings 108 and each of the second (e.g., lower) metallic
fittings 110, thereby facilitating formation of the electrical
grounding paths shown in FIG. 3 and further described below.
FIG. 5 is a perspective view of one of the first metallic fittings
108 of the composite rib 100 of FIGS. 1-4. In FIG. 5, certain
aspects of the first metallic fitting 108 are shown transparently
and/or in phantom to better enable viewing of the component parts
of the first metallic fitting 108. The first (e.g., upper) metallic
fittings 108 of FIGS. 1-5 are structural and/or load-bearing
members of the composite rib 100. In some examples, the first
metallic fittings 108 can be made from aluminum, which is a highly
conductive metal. In other examples, one or more of the first
metallic fittings 108 can alternatively be made from a metal
material other than aluminum including, for example, another highly
conductive metal such as copper or nickel. In the illustrated
example of FIGS. 1-5, each one of the first metallic fittings 108
includes an example plate portion 176 and an example rib portion
178 extending away from the plate portion 176 of the first metallic
fitting 108.
The plate portion 176 of each first metallic fitting 108 of FIGS.
1-5 includes example through holes 180 extending through the plate
portion 176 of the first metallic fitting 108. As further described
below, the through holes 180 of each first metallic fitting 108 are
configured to receive corresponding ones of the first (e.g., upper)
fasteners 112 to facilitate coupling the first metallic fitting 108
to the CFRP panel 102 of the composite rib 100. The first metallic
fittings 108 can include any number of through holes 180
configured, positioned and/or oriented to receive any corresponding
number of first (e.g., upper) fasteners 112, and/or to align with
any corresponding number of through holes formed respectively in
the CFRP panel 102, the hat stiffeners 104, and/or the metallic
grounding plate 106 of the composite rib 100.
When the composite rib 100 of FIGS. 1-4 is in an assembled state
(e.g., as shown in FIGS. 2-4), the first metallic fittings 108 are
coupled to the CFRP panel 102. In some examples, the first metallic
fittings 108 are coupled to the CFRP panel 102 by extending one or
more of the first (e.g., upper) fastener(s) 112 through a
corresponding one or more of the through hole(s) 180 of the first
metallic fittings 108, through a corresponding one or more of the
first (e.g., upper) through hole(s) 172 of the metallic grounding
plate 106, and through a corresponding one or more of the first
(e.g., upper) through hole(s) 140 of the CFRP panel 102. In the
illustrated example of FIGS. 2-4, the plate portion 176 of each one
of the first metallic fittings 108 contacts the second surface 158
of the metallic grounding plate 106. Each one of the first metallic
fittings 108 is positioned along the border 168 of the metallic
grounding plate 106 in a manner that enables formation of the
electrical grounding paths shown in FIG. 3 and further described
below.
The rib portion 178 of each first metallic fitting 108 of FIGS. 1-5
includes an example bore 406 (e.g., a blind hole) that is
configured to receive an example first (e.g., upper) bolt 408. In
the illustrated example of FIGS. 1-5, the bore 406 does not extend
fully through the rib portion 178. As shown in FIGS. 4 and 5, the
bore 406 of each first metallic fitting 108 is oriented
orthogonally relative to the through holes 180 of the first
metallic fitting 108. As shown in FIG. 4, the first bolt 408 is
configured to couple the first metallic fitting 108 and/or, more
generally, the composite rib 100 to the upper skin panel 402 of the
aircraft wing 300. The rib portion 178 of each first metallic
fitting 108 of FIGS. 1-5 further includes an example cavity 410
having an example access opening 412. The cavity 410 of the first
metallic fitting 108 intersects the bore 406 of the first metallic
fitting 108. In the illustrated example of FIGS. 1-5, the cavity
410 does not extend fully through the rib portion 178. As shown in
FIGS. 4 and 5, the cavity 410 is configured to receive an example
barrel nut 414 via the access opening 412 of the first metallic
fitting 108. As shown in FIG. 4, the barrel nut 414 of the first
metallic fitting 108 is positioned within the cavity 410 and
configured to threadably engage the first bolt 408 to couple the
first metallic fitting 108 to the upper skin panel 402 of the
aircraft wing 300.
The rib portion 178 of each first metallic fitting 108 of FIGS. 1-5
further includes an example seal 416 located within the cavity 410.
As shown in FIGS. 4 and 5, the seal 416 of the first metallic
fitting 108 is configured to close and/or fill the access opening
412 of the cavity 410 once the barrel nut 414 has been positioned
within the cavity 410 of the first metallic fitting 108. In some
examples, the seal 416 is configured to prevent electrical sparks
from passing out of the cavity 410 through the access opening 412.
In some examples, the seal 416 interfaces with fuel contained
within the aircraft wing 300.
The second (e.g., lower) metallic fittings 110 of FIGS. 1-4 are
structural and/or load-bearing members of the composite rib 100. In
some examples, the second metallic fittings 110 can be made from
aluminum, which is a highly conductive metal. In other examples,
one or more of the second metallic fittings 110 can alternatively
be made from a metal material other than aluminum including, for
example, another highly conductive metal such as copper or nickel.
In the illustrated example of FIGS. 1-4, each one of the second
metallic fittings 110 includes an example plate portion 182 and an
example rib portion 184 extending away from the plate portion 182
of the second metallic fitting 110.
The plate portion 182 of each second metallic fitting 110 of FIGS.
1-4 includes example first through holes 186 extending through the
plate portion 182 of the second metallic fitting 110. As further
described below, the first through holes 186 of each second
metallic fitting 110 are configured to receive corresponding ones
of the second (e.g., lower) fasteners 114 to facilitate coupling
the second metallic fitting 110 to the CFRP panel 102 of the
composite rib 100. The second metallic fittings 110 can include any
number of first through holes 186 configured, positioned and/or
oriented to receive any corresponding number of second (e.g.,
lower) fasteners 114, and/or to align with any corresponding number
of through holes formed respectively in the CFRP panel 102, the hat
stiffeners 104, and/or the metallic grounding plate 106 of the
composite rib 100.
When the composite rib 100 of FIGS. 1-4 is in an assembled state
(e.g., as shown in FIGS. 2-4), the second metallic fittings 110 are
coupled to the CFRP panel 102. In some examples, the second
metallic fittings 110 are coupled to the CFRP panel 102 by
extending one or more of the second (e.g., lower) fastener(s) 114
through a corresponding one or more of the first through hole(s)
186 of the second metallic fittings 110, through a corresponding
one or more of the second (e.g., lower) through hole(s) 174 of the
metallic grounding plate 106, and through a corresponding one or
more of the second (e.g., lower) through hole(s) 142 of the CFRP
panel 102. In the illustrated example of FIGS. 2-4, the plate
portion 182 of each one of the second metallic fittings 110
contacts the second surface 158 of the metallic grounding plate
106. Each one of the second metallic fittings 110 is positioned
along the border 168 of the metallic grounding plate 106 in a
manner that enables formation of the electrical grounding paths
described below.
The rib portion 184 of each second metallic fitting 110 of FIGS.
1-4 includes an example second through hole 418 that is configured
to receive an example second (e.g., lower) bolt 420. In the
illustrated example of FIGS. 1-4, the second through hole 418 of
each second metallic fitting 110 is oriented orthogonally relative
to the first through holes 186 of the second metallic fitting 110.
As shown in FIG. 4, the second bolt 420 is configured to couple the
second metallic fitting 110 and/or, more generally, the composite
rib 100 to the lower skin panel 404 of the aircraft wing 300. As
further shown in FIG. 4, an example retaining nut 422 is configured
to threadably engage the second bolt 420 to couple the second
metallic fitting 110 to the lower skin panel 404 of the aircraft
wing 300.
The first (e.g., upper) fasteners 112 and the second (e.g., lower)
fasteners 114 can be implemented by and/or as any suitable type of
threaded, partially-threaded, and/or unthreaded fastener including,
for example, bolts, screws, and/or rivets. When the composite rib
100 of FIGS. 1-4 is in an assembled state (e.g., as shown in FIGS.
2-4), one or more of the first (e.g., upper) fastener(s) 112
extend(s) through a corresponding one or more of the through
hole(s) 180 of the first metallic fittings 108, through a
corresponding one or more of the first (e.g., upper) through
hole(s) 172 of the metallic grounding plate 106, through a
corresponding one or more of the first (e.g., upper) through
hole(s) 140 of the CFRP panel 102, and through a corresponding one
or more of the first (e.g., upper) through holes 152 of the hat
stiffeners 104, thereby coupling together the first metallic
fittings 108, the metallic grounding plate 106, the CFRP panel 102,
and the hat stiffeners 104. Similarly, one or more of the second
(e.g., lower) fasteners 114 extend(s) through a corresponding one
or more of the first through hole(s) 186 of the second metallic
fittings 110, through a corresponding one or more of the second
(e.g., lower) through hole(s) 174 of the metallic grounding plate
106, through a corresponding one or more of the second (e.g.,
lower) through hole(s) 142 of the CFRP panel 102, and through a
corresponding one or more of the second (e.g., lower) through holes
154 of the hat stiffeners 104, thereby coupling together the second
metallic fittings 110, the metallic grounding plate 106, the CFRP
panel 102, and the hat stiffeners 104.
In the illustrated example of FIGS. 1-4, the first metallic
fittings 108 are configured to couple the composite rib 100 to the
upper skin panel 402 of the aircraft wing 300, and the second
metallic fittings 110 are configured to couple the composite rib
100 to the lower skin panel 404 of the aircraft wing 300. In other
examples, this orientation can be reversed, with the first metallic
fittings 108 being configured to couple the composite rib 100 to
the lower skin panel 404 of the aircraft wing 300, and the second
metallic fittings 110 being configured to couple the composite rib
100 to the upper skin panel 402 of the aircraft wing 300. In still
other examples, one or more of the second metallic fitting(s) 110
shown in FIGS. 1-4 can be omitted in favor of one or more alternate
metallic fitting(s) structured and/or configured, for example, in a
manner similar to the first metallic fittings 108 of FIGS. 1-5. In
still other examples, one or more of the first metallic fitting(s)
108 shown in FIGS. 1-5 can be omitted in favor of one or more
alternate metallic fitting(s) structured and/or configured, for
example, in a manner similar to the second metallic fittings 110 of
FIGS. 1-4.
In the illustrated example of FIGS. 1-4, respective ones of the
first (e.g., upper) metallic fittings 108 are paired and/or
vertically aligned with corresponding respective ones of the second
(e.g., lower) metallic fittings 110. For example, the first
metallic fittings 108 of FIGS. 1-4 include an example first upper
metallic fitting 188 and an example second upper metallic fitting
190 that is laterally spaced apart from the first upper metallic
fitting 188. The second metallic fittings 110 of FIGS. 1-4 include
an example first lower metallic fitting 192 and an example second
lower metallic fitting 194 that is laterally spaced apart from the
first lower metallic fitting 192. The first upper metallic fitting
188 is paired and/or vertically aligned with the first lower
metallic fitting 192. Similarly, the second upper metallic fitting
190 is paired and/or vertically aligned with the second lower
metallic fitting 194. Pairing and/or vertically aligning respective
ones of the first metallic fittings 108 with corresponding
respective ones of the second metallic fittings 110 advantageously
enables the paired ones of the first and second metallic fittings
108, 110 to be coupled to a single and/or a same corresponding one
of the hat stiffeners 104 of the composite rib 100. For example, as
shown in FIG. 4, the first upper metallic fitting 188 and the first
lower metallic fitting 192 are commonly coupled to an example first
hat stiffener 196 from among the hat stiffeners 104 of the
composite rib 100 of FIGS. 1-4. Similarly, the second upper
metallic fitting 190 and the second lower metallic fitting 194 can
commonly be coupled to an example second hat stiffener 198 from
among the hat stiffeners 104 of the composite rib of FIGS. 1-4.
In the illustrated example of FIG. 3, the composite rib 100 is
shown in an assembled state and coupled to the front spar 302 and
the rear spar 304 of the aircraft wing 300. The first metallic rib
post 306 couples the composite rib 100 to the front spar 302, and
the second metallic rib post 308 coupled the composite rib 100 to
the rear spar 304. Example first CRN cables 310 are carried by,
coupled to, and/or mounted on the front spar 302, and example
second CRN cables 312 are carried by, coupled to, and/or mounted on
the rear spar 304. The first and/or second CRN cables 310, 312 can
lead to and/or be operatively coupled to one or more discharge
probe(s) of the aircraft wing 300 that facilitate dissipating
and/or discharging electrical current and/or electrostatic charge
into the atmosphere.
The first metallic rib post 306 of FIG. 3 is coupled (e.g., bolted,
riveted, etc.) to the CFRP panel 102 of the composite rib 100 at
the first end 120 of the CFRP panel 102. The second metallic rib
post 308 of FIG. 3 is coupled (e.g., bolted, riveted, etc.) to the
CFRP panel 102 of the composite rib 100 at the second end 122 of
the CFRP panel 102. When the composite rib 100 is coupled to the
first and second metallic rib posts 306, 308 as shown in FIG. 3,
the border 168 and/or, more generally, the metallic grounding plate
106 contacts the first and second metallic fittings 108, 110 and
further contacts the first and second metallic rib posts 306, 308,
thereby advantageously providing one or more electrical grounding
paths passing from the first and/or second metallic fittings 108,
110 to the first and/or second metallic rib posts 306, 308 of the
composite rib 100.
In the illustrated example of FIG. 3, the border 168 and/or, more
generally, the metallic grounding plate 106 provides an example
first electrical grounding path 314 that extends from one or more
of the first metallic fittings 108 to the first and/or second
metallic rib posts 306, 308. The border 168 and/or, more generally,
the metallic grounding plate 106 further provides an example second
electrical grounding path 316 that extends from one or more of the
second metallic fittings 110 to the first and/or second metallic
rib posts 306, 308. As shown in FIG. 3, the border 168 of the
metallic grounding plate 106 connects the first and second
electrical grounding paths 314, 316 to one another.
Electrical current (e.g., lightning current from a lightning
strike) and/or electrostatic charge can be received at the first
and/or second metallic fittings 108, 110 of the composite rib 100
from the first and/or second skin panels 402, 404 of the aircraft
wing 300. The first and/or second electrical grounding paths 314,
316 of FIG. 3 can carry and/or pass the received electrical current
and/or electrostatic charge from the first and/or second metallic
fittings 108, 110 of the composite rib 100 to the first and/or
second metallic rib posts 306, 308 of the composite rib 100.
Electrical current and/or electrostatic charge received at the
first metallic rib post 306 passes from the first metallic rib post
306 through the front spar 302 to the first CRN cables 310.
Electrical current and/or electrostatic charge received at the
second metallic rib post 308 passes from the second metallic rib
post 308 through the rear spar 304 to the second CRN cables 312.
The first and/or second CRN cables 310, 312 carry and/or pass the
received electrical current and/or electrostatic charge to one or
more discharge probe(s) of the aircraft wing 300 that facilitate
dissipating and/or discharging electrical current and/or
electrostatic charge into the atmosphere. Thus, the first and
second electrical grounding paths 314, 316 of the composite rib 100
advantageously assist in carrying, passing and/or transferring
electrical current and/or electrostatic charge away from the
composite rib 100 and into the atmosphere.
In the illustrated example of FIG. 4, the composite rib 100 is
shown in an assembled state and coupled to the upper skin panel 402
and the lower skin panel 404 of the aircraft wing 300. The hat
stiffener 104 is coupled to the CFRP panel 102. The flanges 148 of
the hat stiffener 104 contact the first surface 116 of the CFRP
panel 102. The metallic grounding plate 106 is coupled to the CFRP
panel 102. The first surface 156 of the metallic grounding plate
106 contacts the second surface 118 of the CFRP panel 102. The
first (e.g., upper) metallic fitting 108 is coupled to the CFRP
panel 102. The plate portion 176 of the first metallic fitting 108
contacts the second surface 158 of the metallic grounding plate
106. The second (e.g., lower) metallic fitting 110 is coupled to
the CFRP panel 102. The plate portion 182 of the second metallic
fitting 110 contacts the second surface 158 of the metallic
grounding plate 106. The first (e.g., upper) fasteners 112 extend
through the plate portion 176 of the first metallic fitting 108,
through the metallic grounding plate 106, through the CFRP panel
102, and through one of the flanges 148 of the hat stiffener 104.
The second (e.g., lower) fasteners 114 extend through the plate
portion 182 of the second metallic fitting 110, through the
metallic grounding plate 106, through the CFRP panel 102, and
through one of the flanges 148 of the hat stiffener 104.
In the illustrated example of FIG. 4, the assembled composite rib
100 is coupled to the upper skin panel 402 of the aircraft wing 300
via the first (e.g., upper) metallic fitting 108, and coupled to
the lower skin panel 404 of the aircraft wing 300 via the second
(e.g., lower) metallic fitting 110. The coupling of the assembled
composite rib 100 to the upper skin panel 402 of the aircraft wing
300 via the first metallic fitting 108 is provided in part by a
threaded engagement between the first bolt 408 and the barrel nut
414. The coupling of the assembled composite rib 100 to the lower
skin panel 404 of the aircraft wing 300 via the second metallic
fitting 110 is provided in part by a threaded engagement between
the second bolt 420 and the retaining nut 422.
Electrical current (e.g., lightning current) and/or electrostatic
charge applied to the upper skin panel 402 of the aircraft wing 300
is transferred from the upper skin panel 402 to the first (e.g.,
upper) metallic fittings 108 of the composite rib 100, from the
first metallic fittings 108 through the metallic grounding plate
106 (e.g., via the first electrical grounding path 314 of FIG. 3)
to the first and/or second metallic rib posts 306, 308, and from
the first and/or second metallic rib posts 306, 308 through the
front and/or rear spars 302, 304 to the first and/or second CRN
cables 310, 312. Electrical current and/or electrostatic charge
applied to the lower skin panel 404 of the aircraft wing 300 is
transferred from the lower skin panel 404 to the second (e.g.,
lower) metallic fittings 110 of the composite rib 100, from the
second metallic fittings 110 through the metallic grounding plate
106 (e.g., via the second electrical grounding path 316 of FIG. 3)
to the first and/or second metallic rib posts 306, 308, and from
the first and/or second metallic rib posts 306, 308 through the
front and/or rear spars 302, 304 to the first and/or second CRN
cables 310, 312. The first and/or second CRN cables 310, 312 carry
and/or pass the received electrical current and/or electrostatic
charge to one or more discharge probe(s) of the aircraft wing 300
that facilitate dissipating and/or discharging electrical current
and/or electrostatic charge into the atmosphere.
FIG. 6 is an exploded view of an example alternate composite rib
600 constructed in accordance with teachings of this disclosure.
FIG. 7 is a perspective view of the example alternate composite rib
600 of FIG. 6 in an assembled state. The alternate composite rib
600 of FIGS. 6 and 7 includes the CFRP panel 102, the hat
stiffeners 104, the metallic grounding plate 106, the first (e.g.,
upper) metallic fittings 108, the second (e.g., lower) metallic
fittings 110, the first (e.g., upper) fasteners 112, and the second
(e.g., lower) fasteners 114 of the composite rib 100 of FIGS. 1-5
described above. The alternate composite rib 600 of FIGS. 6 and 7
can be coupled to the front and rear spars 302, 304 of the aircraft
wing 300 of FIG. 3 via corresponding ones of the first and second
metallic rib posts 306, 308 of FIG. 3 in the same manner as the
composite rib 100 of FIGS. 1-4 is coupled to the front and rear
spars 302, 304 of the aircraft wing 300 of FIG. 3 via corresponding
ones of the first and second metallic rib posts 306, 308 of FIG. 3,
as described above. Moreover, the alternate composite rib 600 of
FIGS. 6 and 7 can be coupled to the upper skin panel 402 and the
lower skin panel 404 of the aircraft wing 300 of FIG. 4 in the same
manner as the composite rib 100 of FIGS. 1-4 is coupled to the
upper skin panel 402 and the lower skin panel 404 of the aircraft
wing 300 of FIG. 4, as described above.
In addition to the above-identified components and/or parts, the
alternate composite rib 600 of FIGS. 6 and 7 further includes
example first (e.g., upper) shear ties 602 and example second
(e.g., lower) shear ties 604. In the illustrated example of FIGS. 6
and 7, the alternate composite rib 600 includes two (2) first shear
ties 602, and two (2) second shear ties 604. In other examples, the
alternate composite rib 600 can include a different number (e.g.,
0, 1, 3, etc.) of first shear ties 602, and/or a different number
(e.g., 0, 1, 3, etc.) of second shear ties 604. The first and
second shear ties 602, 604 of FIGS. 6 and 7 are structural and/or
load-bearing members of the alternate composite rib 600. In some
examples, the first and second shear ties 602, 604 can be CFRP
shear ties, and can accordingly be made from the same material as
the CFRP panel 102 of the alternate composite rib 600. In other
examples, one or more of the first and second shear ties 602, 604
can alternatively be made from a material other than CFRP
including, for example, a different plastic material and/or a metal
material.
Respective ones of the first (e.g., upper) shear ties 602 are
configured to be coupled to the metallic grounding plate 106
between neighboring ones of the first (e.g., upper) metallic
fittings 108 of the alternate composite rib 600. Similarly,
respective ones of the second (e.g., lower) shear ties 604 are
configured to be coupled to the metallic grounding plate 106
between neighboring ones of the second (e.g., lower) metallic
fittings 110 of the alternate composite rib 600. For example, as
shown in FIG. 7, an example first upper shear tie 606 from among
the first (e.g., upper) shear ties 602 is coupled (e.g., bonded) to
the second surface 158 of the metallic grounding plate 106 at a
location between the first upper metallic fitting 188 and the
second upper metallic fitting 190 from among the first (e.g.,
upper) metallic fittings 108 of the alternate composite rib 600. As
further shown in FIG. 7, an example first lower shear tie 608 from
among the second (e.g., lower) shear ties 604 is coupled (e.g.,
bonded) to the second surface 158 of the metallic grounding plate
106 at a location between the first lower metallic fitting 192 and
the second lower metallic fitting 194 from among the second (e.g.,
lower) metallic fittings 110 of the alternate composite rib 600.
The first and second shear ties 602, 604 of the alternate composite
rib 600 of FIGS. 6 and 7 advantageously enhance the overall
stability of the alternate composite rib 600 relative to that of
the composite rib 100 of FIGS. 1-4 without compromising and/or
impeding the benefits provided by the first and second electrical
grounding paths 514, 516, which remains fully-operable in the
alternate composite rib 600.
From the foregoing, it will be appreciated that example aircraft
wing composite ribs having electrical grounding paths have been
disclosed. The disclosed composite ribs advantageously include a
CFRP panel, a metallic rib post, a metallic fitting, and a metallic
grounding member (e.g., a metallic grounding plate or a metallic
grounding cable). The metallic rib post is coupled to the CFRP
panel and is configured to be coupled to a spar of an aircraft
wing, the spar being coupled to a CRN cable. The metallic fitting
is coupled to the CFRP panel and is configured to be coupled to a
skin panel of the aircraft wing. The metallic grounding member is
positioned between the CFRP panel and the metallic fitting, thereby
advantageously providing an electrical grounding path that extends
from the metallic fitting to the metallic rib post. The electrical
grounding path enables electrical current and/or electrostatic
charge to pass from the metallic fitting to the metallic rib post.
The electrical current and/or electrostatic charge can thereafter
pass from the metallic rib post through the spar to the CRN cable,
thereby allowing for such electrical current and/or electrostatic
charge to be carried and/or dissipated away from the composite rib
and into the atmosphere. The electrical grounding path formed by
the metallic grounding member of the example aircraft wing
composite ribs disclosed herein provides enhanced and/or improved
lightning strike protection without compromising and/or impeding
the above-described benefits associated with implementing a
composite rib having a CFRP panel in lieu of a corresponding
metallic (e.g., aluminum) panel.
In some examples, a composite rib is disclosed. In some disclosed
examples, the composite rib comprises a CFRP panel. In some
disclosed examples, the composite rib further comprises a metallic
rib post coupled to the CFRP panel and configured to be coupled to
a spar of an aircraft wing. In some disclosed examples, the spar is
coupled to a CRN cable. In some disclosed examples, the composite
rib further comprises a metallic fitting coupled to the CFRP panel
and configured to be coupled to a skin panel of the aircraft wing.
In some disclosed examples, the composite rib further comprises a
metallic grounding member positioned between the CFRP panel and the
metallic fitting. In some disclosed examples, the metallic
grounding member provides an electrical grounding path extending
from the metallic fitting to the metallic rib post.
In some disclosed examples, the electrical grounding path is
configured to carry lightning current from the metallic fitting to
the metallic rib post. In some disclosed examples, the lightning
current is to be received at the metallic fitting from the skin
panel, to pass through the electrical grounding path, and to pass
from the metallic rib post through the spar to the CRN cable.
In some disclosed examples, the electrical grounding path is
configured to carry electrostatic charge from the metallic fitting
to the metallic rib post. In some disclosed examples, the
electrostatic charge is to be received at the metallic fitting from
the skin panel, to pass through the electrical grounding path, and
to pass from the metallic rib post through the spar to the CRN
cable.
In some disclosed examples, the metallic grounding member is a
non-structural member.
In some disclosed examples, the metallic fitting is a first
metallic fitting, the skin panel is an upper skin panel, and the
electrical grounding path is a first electrical grounding path. In
some disclosed examples, the composite rib further comprises a
second metallic fitting coupled to the CFRP panel and configured to
be coupled to a lower skin panel of the aircraft wing. In some
disclosed examples, the metallic grounding member is further
positioned between the CFRP panel and the second metallic fitting.
In some disclosed examples, the metallic grounding member provides
a second electrical grounding path extending from the second
metallic fitting to the metallic rib post.
In some disclosed examples, the metallic grounding member is a
metallic grounding plate.
In some disclosed examples, the metallic grounding plate includes a
border and an opening surrounded by the border. In some disclosed
examples, the opening is located between the first and second
metallic fittings. In some disclosed examples, the first and second
metallic fittings contact the border. In some disclosed examples,
the border connects the first and second electrical grounding
paths.
In some disclosed examples, the metallic grounding plate includes a
first surface and a second surface located opposite the first
surface. In some disclosed examples, the first surface contacts the
CFRP panel. In some disclosed examples, the second surface contacts
the first and second metallic fittings.
In some disclosed examples, the composite rib further comprises a
hat stiffener coupled to the CFRP panel.
In some disclosed examples, the CFRP panel includes a first surface
and a second surface located opposite the first surface. In some
disclosed examples, the hat stiffener contacts the first surface of
the CFRP panel, and the metallic grounding plate contacts the
second surface of the CFRP panel.
In some disclosed examples, the hat stiffener is bonded to the
first surface of the CFRP panel. In some disclosed examples, the
metallic grounding plate is bonded to the second surface of the
CFRP panel.
In some disclosed examples, the CFRP panel further includes a
central segment defining a plane, a first flange extending away
from the central segment at a first angle relative to the plane,
and a second flange extending away from the central segment at a
second angle relative to the plane. In some disclosed examples, the
hat stiffener is located between the first flange and the second
flange.
In some disclosed examples, the composite rib further comprises a
first fastener extending through the first metallic fitting, the
metallic grounding plate, the CFRP panel, and the hat stiffener. In
some disclosed examples, the composite rib further comprises a
second fastener extending through the second metallic fitting, the
metallic grounding plate, the CFRP panel, and the hat
stiffener.
In some disclosed examples, the first metallic fitting is a first
upper metallic fitting and the second metallic fitting is a first
lower metallic fitting. In some disclosed examples, the composite
rib further comprises a second upper metallic fitting coupled to
the CFRP panel and configured to be coupled to the upper skin
panel, the second upper metallic fitting being spaced apart from
the first upper metallic fitting. In some disclosed examples, the
composite rib further comprises a second lower metallic fitting
coupled to the CFRP panel and configured to be coupled to the lower
skin panel, the second lower metallic fitting being spaced apart
from the first lower metallic fitting. In some disclosed examples,
the composite rib further comprises a first shear tie coupled to
the metallic grounding plate at a location between the first and
second upper metallic fittings. In some disclosed examples, the
composite rib further comprises a second shear tie coupled to the
metallic grounding plate at a location between the first and second
lower metallic fittings.
In some examples, a method for assembling a composite rib is
disclosed. In some disclosed examples, the method comprises
coupling a metallic grounding member to a CFRP panel. In some
disclosed examples, the method further comprises coupling a
metallic rib post to the CFRP panel. In some disclosed examples,
the metallic rib post is configured to be coupled to a spar of an
aircraft wing. In some disclosed examples, the spar is coupled to a
CRN cable. In some disclosed examples, the method further comprises
coupling a metallic fitting to the CFRP panel. In some disclosed
examples, the metallic fitting is configured to be coupled to a
skin panel of the aircraft wing. In some disclosed examples of the
method, the metallic grounding member is positioned between the
CFRP panel and the metallic fitting, and the metallic grounding
member provides an electrical grounding path extending from the
metallic fitting to the metallic rib post.
In some disclosed examples, the metallic fitting is a first
metallic fitting, the skin panel is an upper skin panel, and the
electrical grounding path is a first electrical grounding path. In
some disclosed examples, the method further comprises coupling a
second metallic fitting to the CFRP panel. In some disclosed
examples, the second metallic fitting is configured to be coupled
to a lower skin panel of the aircraft wing. In some disclosed
examples, the metallic grounding member is further positioned
between the CFRP panel and the second metallic fitting, and the
metallic grounding member provides a second electrical grounding
path extending from the second metallic fitting to the metallic rib
post.
In some disclosed examples, the metallic grounding member is a
metallic grounding plate.
In some disclosed examples, the metallic grounding plate includes a
border and an opening surrounded by the border. In some disclosed
examples, the opening is located between the first and second
metallic fittings. In some disclosed examples, the first and second
metallic fittings contact the border. In some disclosed examples,
the border connects the first and second electrical grounding
paths.
In some disclosed examples, the method further comprises coupling a
hat stiffener to the CFRP panel.
In some disclosed examples, the CFRP panel includes a first surface
and a second surface located opposite the first surface. In some
disclosed examples, the hat stiffener contacts the first surface of
the CFRP panel, and the metallic grounding plate contacts the
second surface of the CFRP panel.
In some disclosed examples, the coupling the hat stiffener to the
CFRP panel includes bonding the hat stiffener to the first surface
of the CFRP panel. In some disclosed examples, the coupling the
metallic grounding plate to the CFRP panel includes bonding the
metallic grounding plate to the second surface of the CFRP
panel.
In some disclosed examples, the coupling the first metallic fitting
to the CFRP panel includes extending a first fastener through the
first metallic fitting, the metallic grounding plate, the CFRP
panel, and the hat stiffener. In some disclosed examples, the
coupling the second metallic fitting to the CFRP panel includes
extending a second fastener through the second metallic fitting,
the metallic grounding plate, the CFRP panel, and the hat
stiffener.
In some examples, a metallic fitting configured to couple a
composite rib to a skin panel of an aircraft wing is disclosed. In
some disclosed examples, the metallic fitting comprises a through
hole configured to receive a fastener, the fastener configured to
couple the metallic fitting to the composite rib. In some disclosed
examples, the metallic fitting further comprises a bore configured
to receive a bolt. In some disclosed examples, the metallic fitting
further comprises a cavity intersecting the bore, the cavity having
an access opening. In some disclosed examples, the metallic fitting
further comprises a barrel nut located within the cavity, the
barrel nut configured to threadably engage the bolt to couple the
metallic fitting to the skin panel. In some disclosed examples, the
metallic fitting further comprises a seal located within the
cavity, the seal configured to close the access opening.
In some disclosed examples, the through hole is orthogonal to the
bore.
In some disclosed examples, the metallic fitting further comprises
a plate portion and a rib portion extending away from the plate
portion.
In some disclosed examples, the through hole is formed in the plate
portion.
In some disclosed examples, the bore is formed in the rib portion.
In some disclosed examples, the bore does not extend fully through
the rib portion.
In some disclosed examples, the cavity is formed in the rib
portion. In some disclosed examples, the cavity does not extend
fully through the rib portion.
In some disclosed examples, the seal is configured to prevent
sparks from passing out of the cavity through the access
opening.
In some disclosed examples, the seal is configured to interface
with fuel contained within the aircraft wing.
In some examples, a method for coupling a composite rib to a skin
panel of an aircraft wing via a metallic fitting is disclosed. In
some disclosed examples, the method comprises extending a fastener
through a through hole of the metallic fitting to couple the
metallic fitting to the composite rib. In some disclosed examples,
the method further comprises extending a bolt into a bore of the
metallic fitting to couple the metallic fitting to the skin panel.
In some disclosed examples, the bolt threadably engages a barrel
nut located within a cavity of the metallic fitting. In some
disclosed examples, the cavity intersects the bore and has an
access opening. In some disclosed examples, the access opening is
closed by a seal located within the cavity.
In some disclosed examples of the method, the through hole is
orthogonal to the bore.
In some disclosed examples of the method, the metallic fitting
includes a plate portion and a rib portion extending away from the
plate portion.
In some disclosed examples of the method, the through hole is
formed in the plate portion.
In some disclosed examples of the method, the bore is formed in the
rib portion. In some disclosed examples, the bore does not extend
fully through the rib portion.
In some disclosed examples of the method, the cavity is formed in
the rib portion. In some disclosed examples, the cavity does not
extend fully through the rib portion.
In some disclosed examples of the method, the seal is configured to
prevent sparks from passing out of the cavity through the access
opening.
In some disclosed examples of the method, the seal is configured to
interface with fuel contained within the aircraft wing.
Although certain example methods, apparatus and articles of
manufacture have been disclosed herein, the scope of coverage of
this patent is not limited thereto. On the contrary, this patent
covers all methods, apparatus and articles of manufacture fairly
falling within the scope of the claims of this patent.
* * * * *